from the little-more-Fourth-for-cellphone-users dept

In the 39-page ruling, US District Judge Phyllis Hamilton notably found that the use of stingray to find a man named Purvis Ellis was a "search" under the Fourth Amendment—and therefore required a warrant.

The DOJ -- despite issuing its own guidance requiring warrants for Stingrays in 2015 -- argued in court earlier this year that no warrant was needed to deploy the Stingray to locate a shooting suspect. It actually recommended the court not reach a conclusion on the Fourth Amendment implications of Stingray use, as it had plenty of warrant exceptions at the ready -- mainly the "exigent circumstances" of locating a suspect wanted for a violent crime.

Unfortunately for the federal government (and all other law enforcement agencies located in the court's jurisdiction), the court declined the DOJ's offer to look the other way on Constitutional issues. It found a Stingray's impersonation of cell tower to obtain real-time location information is a search under the Fourth Amendment.

The court adopts Judge Koh’s reasoning in In re Application for Telephone Information, 119 F. Supp. 3d at 1026, to hold that cell phone users have an expectation of privacy in their cell phone location in real time and that society is prepared to recognize that expectation as reasonable. While Judge Koh limited her analysis to the privacy interest in historical CSLI, the court determines that cell phone users have an even stronger privacy interest in real time location information associated with their cell phones, which act as a close proxy to one’s actual physical location because most cell phone users keep their phones on their person or within reach, as the Supreme Court recognized in Riley. In light of the persuasive authority of Lambis, and the reasoning of my learned colleagues on this court recognizing a privacy interest in historical cell site location information, the court holds that Ellis had a reasonable expectation of privacy in his real-time cell phone location, and that use of the Stingray devices to locate his cell phone amounted to a search requiring a warrant, absent an exception to the warrant requirement.

The court also has something to say about the FBI/Oakland PD's use of a pen register order as a stand-in for a warrant specifically detailing the type of device to used to obtain these so-called "phone records."

The government contends that since the Stingray devices used in this case were configured in compliance with the pen register statute, then the provisions of the pen register statute, including the “emergency” provisions, govern their operation. Doc. no. 321 at 9 (citing 18 U.S.C. § 3125). The government does not address the key issue in dispute, namely, whether the provisions of the pen register statute and the SCA provide the appropriate standard for using a CSS to locate a cell phone in real-time. The court follows Judge Illston’s determination in Cooper, 2015 WL 881578, that the provisions of the pen register statute and the SCA do not authorize the use of a CSS to disclose realtime information about a cell phone user’s physical location, and that such location monitoring must be authorized by a showing of probable cause.

It also points out the DOJ's reliance on the Stored Communications Act to salvage its warrantless Stingray use is misplaced -- something that could be gathered by the name of the statute.

[C]ongress intended that the SCA “was to be used as a means to obtain data which has already been stored at the time the government seeks to obtain it,” as opposed to real-time data.

Ultimately, though, the court denies the suppression of the evidence, allowing the government's "exigent circumstances" argument to prevail. This may prove to be a good thing in the long run (although it does little for the defendant). Allowing the government to keep its evidence gives it no reason to appeal the decision. And this decision implements a warrant requirement for obtaining real-time cell site location info and gives certain third-party records an expectation of privacy.